Saudi Arabia has accused the United States of deceiving the kingdom in striking the nuclear accord with Iran and said it will adopt a "new defence doctrine" focused on resisting Iranian influence in the Middle East.

The Saudi envoy to London, Nawaf Obaid, said that the kingdom officials were not directly briefed on the US contacting directly to Iran through a channel in the Gulf state of Oman, the Gulf News reports.

He said that Washington lied to them, and things were hidden from them.

The statement came after Britain urged the main regional powers to back the agreement signed between the world powers and Iran on Tehran's nuclear programme.

The kingdom's rulers are deeply suspicious of Iran's intentions and of American diplomacy, especially since they were kept in the dark about the US contacts with Iran that preceded the Geneva agreement.